org.apache.spark.scheduler

Class CompressedMapStatus

Object

org.apache.spark.scheduler.CompressedMapStatus

All Implemented Interfaces:

java.io.Externalizable, java.io.Serializable, MapStatus

public class CompressedMapStatus
extends Object
implements MapStatus, java.io.Externalizable

A MapStatus implementation that tracks the size of each block. Size for each block is represented using a single byte.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
CompressedMapStatus(BlockManagerId loc, byte[] compressedSizes)
CompressedMapStatus(BlockManagerId loc, long[] uncompressedSizes)

Method Summary

Methods

Modifier and Type	Method and Description
long	getSizeForBlock(int reduceId) Estimated size for the reduce block, in bytes.
BlockManagerId	location() Location where this task was run.
void	readExternal(java.io.ObjectInput in)
void	writeExternal(java.io.ObjectOutput out)

Methods inherited from class Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CompressedMapStatus

public CompressedMapStatus(BlockManagerId loc,
                   byte[] compressedSizes)

CompressedMapStatus

public CompressedMapStatus(BlockManagerId loc,
                   long[] uncompressedSizes)

Method Detail

location

public BlockManagerId location()

Description copied from interface: MapStatus

Location where this task was run.

Specified by:

location in interface MapStatus

getSizeForBlock

public long getSizeForBlock(int reduceId)

Description copied from interface: MapStatus

Estimated size for the reduce block, in bytes.

If a block is non-empty, then this method MUST return a non-zero size. This invariant is necessary for correctness, since block fetchers are allowed to skip zero-size blocks.

Specified by:

getSizeForBlock in interface MapStatus

writeExternal

public void writeExternal(java.io.ObjectOutput out)

Specified by:

writeExternal in interface java.io.Externalizable

readExternal

public void readExternal(java.io.ObjectInput in)

Specified by:

readExternal in interface java.io.Externalizable